Morphological and Mechanical Properties of Two Alcyonaceans, Sinularia Flexibilis and S. Capillosa

兩種指形軟珊瑚之形態和機械特性

林明炤(Ming-Chao Lin) ； 戴昌鳳(Chang-Feng Dai)

《Zoological Studies》 36卷1期 (1997/01) Pp. 58-63

摘要

本研究以生物力學的方法，分析柔軟指形軟珊瑚（Sinularia flexibilis）、條狀指形軟珊瑚（S. capillosa）的群體形態、機械特性和水流的關係。首先，以這兩種軟珊瑚的群體進行阻力實驗，於不同流速下，記錄珊瑚所承受的阻力和群體形態的改變，再取珊瑚的柱部組織，進行拉伸力試驗，測量應力和形變，推算珊瑚組織的彈性係數。結果顯示，這兩種軟珊瑚具有相似的形態和機械特性，其柔度使群體容易順應水流而變形，在較高的流速下，由於群體趨於流線形並倒向基底，可使阻力的作用減小。另外，這兩種軟珊瑚也具有相似的骨針含量和群體勁度，但它們的骨針大小和中膠層勁度卻不同，顯示骨針可能不是影響群體勁度的主要因子，中膠層勁度也許扮演著更重要的角色。因此，雖然這兩種軟珊瑚具有相似的形態和機械特性，但它們卻是藉著不同的支持構造減小阻力的作用。

關鍵字

生物力學 ； 阻力 ； 骨針 ； 水流

並列摘要

Drag and changes of colony morphology under various flow velocities of 2 sympatric alcyonaceans, Sinularia flexibilis and S. capillosa, were studied. The mechanical properties of tissues from these 2 species were also investigated. Colonies of the 2 species have similar mophological and mechanical properties. Flexibility of the colonies enables them to bend into a drag-reducing orientation at higher flow velocities by collapsing the colony, thus bringing it nearer the substratum. In addition, the 2 species also have a similar volume fraction of sclerites and similar stiffness of intact colony tissue. However, the 2 species differ in sclerite size, and the stiffness of S. flexibilis after decalcification is higher than that of S. capillosa. These facts indicate that sclerites may not be the only factor affecting the stiffness of S. flexibilis and S. capillosa; the stiffness of the mesoglea may also play an important role. The results show that these 2 sympatric species possess similar morphological and mechanical properties to reduce drag, but they achieve this through different skeletal constitutions.

並列關鍵字

Biomechanics ； Drag ； Sclerite ； Water flow